Try in the Wiki, Saunders89 put a list of web sites where to get seed catalogues from, just go on line, order the catalogues and spend hours and hours reading and dreaming. I'm not sure but but if you do a search in A4A, someone, maybe jerry again, put a list of veg and the prices from different suppliers.
Sorry should have said go to Wiki - click on seeds, then click on seed catalogues, list of seed merchants web sites.